Design, Manufacturing and Acoustic Assessment of Polymer Mouthpieces for Trombones.

Brass instruments mouthpieces have been historically built using metal materials, usually brass. With the auge of additive manufacturing technologies new possibilities have arisen, both for testing alternative designs and for using new materials. This work assesses the use of polymers for manufacturing trombone mouthpieces, specifically PLA and Nylon. The acoustical behavior of these two mouthpieces has been compared with the obtained from a third one, built from brass. Both additive and subtractive manufacturing techniques were used, and the whole manufacturing process is described. The mouthpieces were acoustically assessed in an anechoic chamber with the collaboration of a professional performer. The harmonic analysis confirmed that all the manufactured mouthpieces respect the harmonic behavior of the instrument. An energy analysis of the harmonics revealed slight differences between the mouthpieces, which implies differences in the timbre of the instrument. Although these subtle differences would not be acceptable when performing with the instrument in an orchestra, they could be perfectly valid for early learners, personal rehearsals or any kind of alternative performance.

The Environmental Impacts of Disposable Nonwoven Fabrics during the COVID-19 Pandemic: Case Study on the Francesc de Borja Hospital.

Hospitals generate huge amounts of nonwoven residues daily. This paper focused on studying the evolution of nonwoven waste generated in the Francesc de Borja Hospital, Spain, over the last few years and its relation to the COVID-19 pandemic. The main objective was to identify the most impacting pieces of nonwoven equipment in the hospital and to analyze possible solutions. The carbon footprint of the nonwoven equipment was studied through a life-cycle assessment. The results showed an apparent increase in the carbon footprint in the hospital from 2020. Additionally, due to the higher annual volume, the simple nonwoven gown used primarily for patients had a higher carbon footprint over a year than the more sophisticated surgical gowns. It can be concluded that developing a local circular economy strategy for medical equipment could be the solution to avoid the enormous waste generation and the carbon footprint of nonwoven production.

Telemedicina en el control de la hipertensión arterial

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Introduction: Arterial hypertension is the great challenge of health policies in the world. Its high prevalence, the lack of control (linked to poor adherence to antihypertensive treatment) and its high "burden" (as a non-communicable disease) are responsible for the increase in cardiovascular morbidity and mortality. Objetive: To evaluate, as a pilot test, the benefit of real-time telemonitoring applied to blood pressure (BP) control. Metodology: Inclusion criteria: Diagnosed hypertensives, under pharmacological treatment, assisted in the Maciel Hospital polyclinic in the period June-October 2019. Exclusion criteria: pregnancy and upper arm circumference less than 22 cm or greater than 42 cm. Home blood pressure monitoring was implemented, using a validated electronic blood pressure monitor and a smart cell phone connected to a private web platform in real time. Analytical, experimental, prospective study. Qualitative variables were expressed in absolute frequency and percentage relative frequency. Quantitative variables were expressed as mean and standard deviation. The normality of the distribution was verified using the Kolmogorov Smirnov test. Results: Of a total of 57 patients, the mean age was 59 ± 12.8 years, female sex 64.9%. Presenting 22.8% poor knowledge of the disease. Regarding the control of BP figures, 31.6% reported not checking regularly. Adherence to pharmacological treatment at the beginning of the monitoring was 33.3%. Figures lower than those described by RENATA-2, where half of the treated hypertensives complied with the treatment. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were analyzed at the beginning and end of the study. Pre-monitoring measurements were mean SBP: 138.6 ± 17.8 mmHg and mean DBP: 85.4 ± 14.8 mmHg. The records at the end of the immediate monitoring were 131.5 ± 19.9 mmHg and 81.5 ± 14.2 mmHg for PAS and PAD, respectively. Finding a significant difference between the means of the PAS (p 0.019), but not between the means of the DBP (p 0.06). Discussion: Although the percentage of patients achieving good BP control was significant, these results may be closely related to a subtype of observed performance bias, rather than the outcome of the intervention. The mean days of telemonitoring were 8, 85, number of shots was 34.12, and number of interventions performed by the observer (medication change) was 0.30. User satisfaction with the method used was 96.4%, and 100% considered it Easy or very easy to use. 87.5% would use it for long periods of time, including older adults. Conclusions: The studied method shows potential benefits for the control of BP figures, with a wide acceptance by users, facilitating access to the health system, and quality medical care.

Introdução: A hipertensão arterial é o grande desafio das políticas de saúde no mundo. Sua alta prevalência, o descontrole (ligado à baixa adesão ao tratamento anti-hipertensivo) e sua alta "carga" (como doença não transmissível) são responsáveis ​​pelo aumento da morbimortalidade cardiovascular. Objetivo: foi avaliar como teste piloto, o benefício do telemonitoramento em tempo real, aplicado ao controle da pressão arterial (PA). Metodologia: Critérios de inclusão: Hipertensos diagnosticados, em tratamento farmacológico, atendidos na policlínica do Hospital Maciel no período de junho a outubro de 2019. Critérios de exclusão: gravidez e circunferência do braço menor que 22 cm ou maior que 42 cm. Foi implementado o monitoramento domiciliar da pressão arterial, utilizando um monitor eletrônico de pressão arterial validado e um telefone celular inteligente conectado a uma plataforma web privada em tempo real. Estudo analítico, experimental, prospectivo.As variáveis ​​qualitativas foram expressas em frequência absoluta e frequência relativa percentual. As variáveis ​​quantitativas foram expressas como média e desvio padrão. A normalidade da distribuição foi verificada por meio do teste de Kolmogorov Smirnov. Resultados: De um total de 57 pacientes, a média de idade foi de 59 ± 12,8 anos, sexo feminino 64,9%. Apresentando 22,8% conhecimento ruim sobre a doença. Em relação ao controle dos valores da PA, 31,6% relataram não verificar regularmente. A adesão ao tratamento farmacológico no início do acompanhamento foi de 33,3%, valores inferiores aos descritos pelo RENATA-2, onde metade dos hipertensos tratados aderiu ao tratamento. A pressão arterial sistólica (PAS) e a pressão arterial diastólica (PAD) foram analisadas no início e no final do estudo. As medições de pré-monitoramento foram PAS média: 138,6 ± 17,8 mmHg e PAD média: 85,4 ± 14,8 mmHg. Os registros ao final do monitoramento imediato foram de 131,5 ± 19,9 mmHg e 81,5 ± 14,2 mmHg para PAS e PAD, respectivamente. Encontrando diferença significativa entre as médias do PAS (p 0,019), mas não entre as médias do DBP (p 0,06). Discussão: Embora a porcentagem de pacientes que alcançaram um bom controle da PA tenha sido significativa, esses resultados podem estar intimamente relacionados a um subtipo de viés de desempenho observado, e não ao resultado da intervenção. A média de dias de telemonitoramento foi 8, 85, o número de disparos foi 34,12, e o número de intervenções realizadas pelo observador (mudança de medicação) foi de 0,30. A satisfação dos usuários com o método utilizado foi de 96,4%, sendo que 100% consideraram fácil ou muito fácil de usar. 87,5% usariam por longos períodos de tempo, inclusive idosos adultos. Conclusões: O método estudado apresenta potenciais benefícios para o controle dos valores da PA, com ampla aceitação pelos usuários, facilitando o acesso ao sistema de saúde e assistência médica de qualidade.

Life-Cycle Assessment and Acoustic Simulation of Drywall Building Partitions with Bio-Based Materials.

The ecological transition is a process the building industry is bound to undertake. This study aimed to develop new bio-based building partition typologies and to determine if they are suitable ecological alternatives to the conventional non-renewable ones used today. This work started with the development of a bio-based epoxy composite board and a waste-based sheep wool acoustic absorbent. Six different partition typologies combining conventional and bio-based materials were analyzed. A drywall partition composed of gypsum plasterboard and mineral wool was used as the baseline. First, a cradle-to-gate life cycle assessment was performed to compare their environmental impacts. Secondly, a mathematical simulation was performed to evaluate their airborne acoustic insulation. The LCA results show a 50% decrease in the amount of CO2 equivalent emitted when replacing plasterboard with bio-composite boards. The bio-composites lower the overall environmental impact by 40%. In the case of the acoustic absorbents, replacing the mineral wool with cellulose or sheep wool decreases the carbon emissions and the overall environmental impact of the partition from 4% and 6%, respectively. However, while the bio-based acoustic absorbents used offer good acoustic results, the bio-composites have a lower airborne acoustic insulation than conventional gypsum plasterboard.

Sound Absorption Properties of Perforated Recycled Polyurethane Foams Reinforced with Woven Fabric.

The acoustic properties of recycled polyurethane foams are well known. Such foams are used as a part of acoustic solutions in different fields such as building or transport. This paper aims to seek improvements in the sound absorption of these recycled foams when they are combined with fabrics. For this aim, foams have been drilled with cylindrical perforations, and also combined with different fabrics. The effect on the sound absorption is evaluated based on the following key parameters: perforation rate (5% and 20%), aperture size (4 mm and 6 mm), and a complete perforation depth. Experimental measurements were performed by using an impedance tube for the characterization of its acoustic behavior. Sound absorption of perforated samples is also studied-numerically by finite element simulations, where the viscothermal losses were considered; and analytically by using models for the perforated foam and the fabric. Two textile fabrics were used in combination with perforated polyurethane samples. Results evidence a modification of the sound absorption at mid frequencies employing fabrics that have a membrane-type acoustic response.

Utilidad de las técnicas de biología molecular en neuroinfecciones / Usefulness of molecular biology techniques in neuroinfectious diseases / Utilidade das técnicas de biologia molecular em neuroinfecções

Resumen: Introducción: un porcentaje de las infecciones del sistema nervioso central permanece sin diagnóstico etiológico. Las técnicas de amplificación de ácidos nucleicos mediante reacción en cadena de la polimerasa en tiempo real pueden disminuir este porcentaje. Objetivo: describir la etiología de las neuroinfecciones y valorar la utilidad de las técnicas de biología molecular en el diagnóstico y su impacto en el tratamiento antimicrobiano. Metodología: estudio observacional, descriptivo, retrospectivo a partir de registros clínicos. Se incluyeron mayores de 18 años asistidos en un hospital público de Montevideo durante un período de 32 meses, a quienes que se les realizaron técnicas de biología molecular en líquido cefalorraquídeo por sospecha clínica de neuroinfección. Resultados: se incluyeron 109 pacientes. En pacientes sin infección por VIH ni antecedentes neuroquirúrgicos (67%), se identificó microorganismo responsable en 16 casos, 8 bacterias y 9 virus. Todos identificados por técnicas de biología molecular modificando el tratamiento antimicrobiano empírico en 25 casos (34,2%). En portadores de VIH (25,7%), se detectaron microorganismos en 14 pacientes (50%). Seis virus, 5 bacterias y 7 hongos (Cryptococcus neoformans). El estudio por técnicas de biología molecular determinó el diagnóstico de 17 microorganismos y modificó el plan antimicrobiano inicial en 12 casos (42,9%). En pacientes con antecedente de neurocirugía reciente (7,3%), se aislaron seis microorganismos, tres de ellos exclusivamente mediante cultivo. Se modificó el tratamiento en tres casos (37,5%). Conclusiones: las técnicas de biología molecular deben considerarse complementarias. El impacto que generan en el diagnóstico y tratamiento justifica el uso de estas técnicas a pesar de su mayor costo.

Summary: Introduction: a certain percentage of infections of the central nervous system have no etiological diagnosis. Nucleic acids amplification techniques by means of a polymerase chain reaction in real time may reduce this percentage. Objective: to describe etiology of neuroinfectious diseases and assess the usefulness of molecular biology techniques in their diagnosis, as well as its impact on antimicrobial treatment. Method: observational, descriptive, retrospective study based on clinical records which included patients older than 18 years old, who had been assisted in a public hospital in Montevideo for over 32 months and had undergone molecular biology techniques with cerebrospinal fluid (CSF) given the clinical suspicion of neuroinfection. Results: 109 patients were included in the study. Among non-HIV infected patients who had not undergone neurosurgeries the responsible microorganism was identified in 16 cases (8 bacteria and 9 virus). They were all identified by molecular biology techniques by modifying the empiric antimicrobial therapy in 25 cases (34.2%). In carriers of HIV (25.7%), microorganisms were identified in 14 patients (50%). Six virus, 5 bacteria and 7 fungi (Cryptococcus neoformans). Molecular biology techniques defined the diagnosis of 17 microorganisms and modified the initial antimicrobial plan in 12 cases (42.9%). In patients with a history of recent neurosurgery (7.3%), 6 microorganisms were isolated, 3 of them exclusively through cultures. Treatment was modified in 3 cases (37.5%). Conclusions: molecular biology techniques need to be regarded as a complement. The impact that have in diagnosis and therapy justify their use despite its higher cost.

Resumo: Introdução: uma proporção das infecções do sistema nervoso central permanece sem diagnóstico etiológico. As técnicas de ampliação de ácidos nucléicos por reação em cadeia da polimerase em tempo real, podem diminuir esta proporção. Objetivo: descrever a etiologia das neuro infecções e avaliar a utilidade das técnicas de biologia molecular no diagnóstico e seu impacto no tratamento antimicrobiano. Metodologia: estudo observacional, descritivo, retrospectivo de prontuários de pacientes. Foram incluídos pacientes maiores de 18 anos, atendidos em um hospital público de Montevidéu, durante um período de 32 meses. Foram realizadas técnicas de biologia molecular ao líquido cefalorraquidiano por suspeita clínica de neuroinfecção. Resultados: foram incluídos 109 pacientes. Em pacientes sem infecção por VIH e sem antecedentes neurocirúrgicos (67%), o microrganismo responsável em 16 casos, sendo 8 bactérias e 9 vírus. Todos foram identificados por técnicas de biologia molecular modificando el tratamento antimicrobiano empírico em 25 casos (34,2%). Em portadores de VIH (25,7%), foram detectados microrganismos em 14 pacientes (50%). Seis vírus, 5 bactérias e 7 leveduras (Cryptococcus neoformans). O estudo por técnicas de biologia molecular permitiu o diagnóstico de 17 microrganismos e modificou o tratamento antimicrobiano inicial em 12 casos (42,9%). Em pacientes com antecedentes de neurocirurgia recente (7,3%), foram isolados 6 microrganismos, em 3 casos exclusivamente por cultura. O tratamento foi modificado em 3 casos (37,5%). Conclusões: as técnicas de biologia molecular devem ser consideradas como complementares. O impacto que causam sobre o diagnóstico e o tratamento justifica seu uso apesar de seu maior custo.

Characterization of Sheep Wool as a Sustainable Material for Acoustic Applications.

In recent years, natural materials are becoming a valid alternative to traditional sound absorbers due to reduced production costs and environmental protection. This paper reports the acoustical characterization of sheep wool. Measurements on normal incidence and diffuse-incidence sound absorption coefficients of different samples are reported. The airflow resistance has also been measured. The results prove that sheep wool has a comparable sound absorption performance to that of mineral wool or recycled polyurethane foam. An empirical model is used to calculate the sound absorption of sheep wool samples. A reasonable agreement on the acoustic absorption of all sheep wool samples is obtained.

Vibroacoustic Impact on the Architectonic Heritage When Using Replicas of 16th Century Weapons.

The recreation of historical battles next to old buildings, walls, churches, fortifications or historical facades belonging to the historical heritage of a city, has always been a source of controversy and discussion. In the absence of a clear legislation about how these buildings can be affected by the use of blunderbusses and pyrotechnics, it is necessary to carry out practical experiments to test the effect of these celebrations on these buildings. For this reason, this paper presents a set of practical experiments where the vibroacoustic effect of using weapons such as blunderbusses and harquebuses is analyzed. To gather these measurements, we have used several sound level meters and 3-axis accelerometers placed on the facade of an old building. The tests have been carried out at the Moors and Christians festival of Villajoyosa (Spain) which is internationally famous for this festival. In order to carry out the tests, six harquebusiers shot their firearms and the sensors placed along the facade of the building at different height collected the data. The results of these devices allow us to study the vibroacoustic impact on the facade depending on the height.

Effect of Sodium Hydroxide Treatments on the Tensile Strength and the Interphase Quality of Hemp Core Fiber-Reinforced Polypropylene Composites.

The formulation of greener composite materials by substituting glass fibers with natural fibers is a current field of research. If such natural fiber reinforcements come from industrial side streams, as hemp core fibers (HCFs) come from the extraction of hemp strands for the textile industry, an additional advantage can be identified. Nonetheless, such by-product fibers show some drawbacks, such as high lignin contents, which can make it difficult to obtain a good interphase between the fibers and the matrix and to obtain a good fiber individualization. A digestion treatment at different NaOH contents is proposed to eliminate soluble lignin and extractives from the surface of the fibers. At the same time, the use of a coupling agent solves incompatibilities between the fibers and the matrix. The composites were tensile tested and the impact of the proposed treatments is evaluated and discussed. Later, the Kelly-Tyson modified equation and a modified rule of mixtures-the micro-mechanic models-is used to study the impact of such treatments on the quality of the interphase between the polymer and the reinforcement. Both treatments showed a high impact on the tensile strength and the quality of the interphase, obtaining competitive composite materials reinforced with HCFs derived from a by-product.